At present, display screens of more and more mobile phones have a structure with a narrow frame. A primary technique for accomplishing a narrow frame for Thin Film Transistor-Liquid Crystal Display (TFT-LCD) in a display screen is a gate driving technique, which achieves the purpose of making TFT-LCD of the display screen have the narrow fame by a manner of omitting gate fan-out. As compared to other techniques, such gate driving technique does not require introducing a new optical mask or adding any additional process, and thus it is fully compatible with existing manufacturing process of TFT-LCD. In addition, cost for manufacturing the gate driving circuit is low and reliability is high. Due to the above reasons, the gate driving technique has become the primary technique for accomplishing the narrow frame for TFT-LCD at present.
The existing gate driving circuit mainly includes shift register units and an inverter having functions of pulling up an electrical potential (that is, increasing the electrical potential of an output terminal) and pulling down the electrical potential (that is, decreasing the electrical potential of the output terminal). The basic operational principle of the existing gate driving circuit is as follows: inputting a square wave having a certain width by inputting Integrated Circuit (IC) signal, scanning pixels in each of rows from up to down, and representing output voltages of pixels of the scanned row in a square wave. The operational principle of an existing shift register unit circuit is as shown in FIG. 1. Since a clock signal CLK1 in such shift register unit circuit is in series connected to a capacitor C1 having a big capacitance, power consumption of the circuit will be increased. In addition, an output terminal Row(n) is in a floating state most of the time with the electrical potential thereof not being pulled down, there are many burrs and miscellaneous spikes in the waveform of the output voltage of the output terminal Row(n), thus quality of display being reduced.